1. Field of the Invention
The invention relates to a connection between a ladder side rail and a hinged arm of a ladder hinge.
2. Brief Description of the Background of the Invention Including Prior Art
Presently the connection between the ladder side rails and the two hinged arms of the ladder hinge is produced nearly exclusively through rivet connections. Either rivets passing through or blind rivets are employed in this situation, wherein the rivets are exclusively entered at the longer sides of the profiles, which profiles are disposed perpendicular to the hinge axis and perpendicular to the force engagement of case of a load. It is a disadvantage in connection with the rivet connections that they exhibit a relatively small supporting face and a play between the rivets and the boreholes, whereby a one-sided resting of the rivet at the borehole results in case of a load, and where a deformation of the borehole can occur based on the rounding of the borehole. In order to assure the required safety, relatively many rivet connections are required. A method and a device for the connection of at least two construction parts is described in the German printed patent document DE 43 44 921 A1, which method and device amongst others can be applied also to the generation of a connection between a ladder side rail and a hinge arm of a ladder hinge. Boreholes are entered in the hinged arm and in the ladder side rail, wherein the material of an addition profile element is entered in the boreholes with the aid of a bolt, wherein the bolt remains in the ladder side rail. In this case also the joining connection is entered at the sides of the profile, which are disposed perpendicular to the hinge axis and to the force engagement.
The hinge arms and the ladder side rails have to overlap over a relatively large region according to the known kinds of connection. Furthermore, in case of an overload, which can occur by a lever action between the ladder side rail and the hinged arm, there can occur an undesired deformation at the end of the ladder side rail. In this case, the ladder side rail expands at the narrow side, where the hinged arm is pressed against said narrow side in case of a load.